The present disclosure provides a piston for an internal combustion engine, the piston having a piston body including a first bearing saddle defining a first axis and a second bearing saddle defining a second axis, the first axis being parallel to and spaced from the second axis. A bearing is also provided, the bearing having a first journal having a first body, longitudinal ends, and lateral edges, the first journal defining a first axis, the first journal disposed about approximately 180 degrees of the first axis and a second journal having a second body and defining a second axis, the second journal disposed about approximately 180 degrees of the second axis, the second journal operable to be positioned abutting one of the lateral edges of the first journal when the first and second journals are positioned with the piston.

A wear-preventive air-charger piston structure is provided. The piston rod has a top forming a piston top seat on which a piston ring is disposed. The piston ring is covered with a top cover that is combined with the piston top seat. The top cover is provided with an airtight plate mounted thereto to form a complete piston structure. A buffering element is arranged between the piston top seat and the piston ring. The buffering element has an outside diameter smaller than the piston ring, so that when the piston ring, which is driven by a crankshaft to do an up-and-down movement, is put in an inclined oscillating condition and at a high position of an oscillation side, the buffering element functions to absorb the stress acting on the piston ring at the high position of the oscillation side to effectively prevent detachment and breaking of the piston ring.

A wear-preventive air-charger piston structure is provided. The piston rod has a top forming a piston top seat on which a piston ring is disposed. The piston ring is covered with a top cover that is combined with the piston top seat. The top cover is provided with an airtight plate mounted thereto to form a complete piston structure. A buffering element is arranged between the piston top seat and the piston ring. The buffering element has an outside diameter smaller than the piston ring, so that when the piston ring, which is driven by a crankshaft to do an up-and-down movement, is put in an inclined oscillating condition and at a high position of an oscillation side, the buffering element functions to absorb the stress acting on the piston ring at the high position of the oscillation side to effectively prevent detachment and breaking of the piston ring.

A wear-preventive air-charger piston structure is provided. The piston rod has a top forming a piston top seat on which a piston ring is disposed. The piston ring is covered with a top cover that is combined with the piston top seat. The top cover is provided with an airtight plate mounted thereto to form a complete piston structure. A buffering element is arranged between the piston top seat and the piston ring. The buffering element has an outside diameter smaller than the piston ring, so that when the piston ring, which is driven by a crankshaft to do an up-and-down movement, is put in an inclined oscillating condition and at a high position of an oscillation side, the buffering element functions to absorb the stress acting on the piston ring at the high position of the oscillation side to effectively prevent detachment and breaking of the piston ring.

A wear-preventive air-charger piston structure is provided. The piston rod has a top forming a piston top seat on which a piston ring is disposed. The piston ring is covered with a top cover that is combined with the piston top seat. The top cover is provided with an airtight plate mounted thereto to form a complete piston structure. A buffering element is arranged between the piston top seat and the piston ring. The buffering element has an outside diameter smaller than the piston ring, so that when the piston ring, which is driven by a crankshaft to do an up-and-down movement, is put in an inclined oscillating condition and at a high position of an oscillation side, the buffering element functions to absorb the stress acting on the piston ring at the high position of the oscillation side to effectively prevent detachment and breaking of the piston ring.

Various implementations include a combustion engine piston, including a skirt in a counter-part and including a first contact area of the piston in the counter-part, a head which extends transverse to a central axis, and a ring carrier which comprises at least two lands and at least two grooves for receiving the rings, including a first land adjoining the head and a second land situated between the first land and the skirt, wherein the lands include at least one contact land having a diameter greater than a minimum diameter of the skirt to form a second contact area of the piston in the counter-part, and wherein at least one contact land comprises a friction-reducing surface coating, formed at least on a radial sector covering an angle of at least 30 degrees, and up to on a single sector covering an angle of 360 degrees.

Various implementations include a combustion engine piston, including a skirt in a counter-part and including a first contact area of the piston in the counter-part, a head which extends transverse to a central axis, and a ring carrier which comprises at least two lands and at least two grooves for receiving the rings, including a first land adjoining the head and a second land situated between the first land and the skirt, wherein the lands include at least one contact land having a diameter greater than a minimum diameter of the skirt to form a second contact area of the piston in the counter-part, and wherein at least one contact land comprises a friction-reducing surface coating, formed at least on a radial sector covering an angle of at least 30 degrees, and up to on a single sector covering an angle of 360 degrees.

A piston and cylinder assembly of an axial piston machine is disclosed which includes a cylinder having a uniform internal diameter, a cylindrical bushing press-fit against the inner surface of the cylinder and extending at least partially therein, the bushing comprising at least one circumferential groove formed on an outer surface of the bushing against the inner surface of the cylinder, a piston reciprocably disposed within the cylindrical bushing, generating a piston-bushing-interface, the piston and the bushing defining a diametrical clearance therebetween, the diametrical clearance defining a lubrication gap and a fluid-dynamic seal between the piston and the cylindrical bushing.

A piston and cylinder assembly of an axial piston machine is disclosed which includes a cylinder having a uniform internal diameter, a cylindrical bushing press-fit against the inner surface of the cylinder and extending at least partially therein, the bushing comprising at least one circumferential groove formed on an outer surface of the bushing against the inner surface of the cylinder, a piston reciprocably disposed within the cylindrical bushing, generating a piston-bushing-interface, the piston and the bushing defining a diametrical clearance therebetween, the diametrical clearance defining a lubrication gap and a fluid-dynamic seal between the piston and the cylindrical bushing.

A piston for a compressor includes a bearing portion having a cylindrical shape to define a suction space into which refrigerant is accommodated therein, the bearing portion being provided with a bearing surface facing an inner circumferential surface of the cylinder, a head portion coupled to a front opening of the bearing portion and provided with a plurality of suction ports which communicate with the suction space, the head portion having a compression surface configured to face a compression space to compress the refrigerant in the compression space, and a flange portion coupled to a rear opening of the bearing portion and provided with a through-passage through which the refrigerant is introduced from a muffler unit to the suction space, the flange portion being coupled to a driving portion to transmit driving force to the piston. The bearing surface is subjected to a surface treatment to improve abrasion resistance.